The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventor(s), to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Many data storage systems (e.g., disk drives) employ some type of coding system in which data being stored is combined, or encoded, with redundant information to form a codeword that meets a priori established constraints. Codewords that are received or retrieved from memories (e.g., read from a hard disk drive sector) are checked against the constraints to determine if the codeword has been correctly read. If the codeword does not meet the constraints, several techniques may be used to attempt to correct the codeword. One popular technique is to use codes that are amenable to iterative decoding approaches, and correct the codeword via iterative decoding techniques.